Currently, as for the interoperability between the HRPD network and the 1x network, especially relating to the deliver y of the mobile terminated paging from the 1x network in the HRPD system, the following methods are adopted in the prior art:
When IWS (Interworking Solution) is during the AN (Access Network), as shown in FIG. 1, this call flow is described as follows:
101: MSC (Mobile Switching Center) determines that an incoming call terminates to an MS/AT within its serving region. The MSC sends a Paging Request message to the HRPD AN (HRPD system access network) and one or more 1x BSs reachable by an MS/AT within the AN's paging area. The MSC starts an instance of timer T3113 for each Paging Request message sent.
MSC can include calling party information. Meanwhile, the paging request message can contains a “VPI (Visual Paging Indicator)” identifying that the 1x BS shall prepare to accept the paging response message from the MS/AT.
102: HRPD AN sends a “GPM (General Paging Message)” to the MS/AT. If the MSC includes calling party information, the IWS-1xBS includes a Feature Notification Message containing the calling party information in the same message.
103: The MS/AT is tuned to the 1x system and sends a paging response message via 1x access channel.
104: The 1x BS puts the paging response message in the Complete L3 Info message and sends the same to MSC. If the paging request message contains a Tag information unit, the 1x BS shall put this information unit in the paging response message. MS/AT default is that it is registered in the 1x system. MSC stops all the instances of timers T3113 for this MS/AT.
105: 1x BS/MSC continues the establishment process for calling the mobile station.
106: MSC can determine that the MS/AT subscribing for a “Cross Notification” service function has been registered in the 1x system, send an “Event Notification” message including the registration event to the HRPD AN, and start the timer Tevent. This step may occur at any time after the step “104”.
107: After receiving the Event Notification message, the HRPD AN sends an event notification acknowledgement (Ack) message to MSC. Upon receiving this message, MSC stops the timer Tevent.
When IWS is located in 1x BS, as shown in FIG. 2, this flow is detailed as follows:
201: MSC finds a call terminated by the AT/MS in its service area, and then sends a paging request message to 1x IWS-BS, and starts an instance of timer T3113.
202: IWS-1xBS sends an A21-1x Air Interface Signaling message to the AN of HRPD, starts the timer Tack-21, and this message includes 1x paging message. Before requiring the HRPD to page the MS/AT, IWS-1xBS ensures that the resource supporting 1x service is available.
203: HRPD AN sends 1x paging message to the MS/AT.
204: The MS/AT acknowledges the receipt of the 1x paging message.
205: HRPD AN sends an A21 interface Ack (A21-Ack) message to IWS-1x BS, to acknowledge the receipt of the A21 message. IWS-1x BS stops the timer Tack-21. If HRPD AN does not find the AT/MS, the A21-Ack message includes a reason value being “Unknown MS/AT”, and the call flow ends.
206: The MS/AT is tuned to 1x system and sends a paging response message at the 1x access channel to acknowledge the paging.
207: 1x BS constructs a paging response message which is put in the Complete 3L Info message and sends the same to MSC. If the paging response message includes a Tag information unit, 1x BS includes the same Tag information unit in the paging response message. MSC stops all the instance of timers T3113 related to this AT/MS.
208: 1x BS/MSC continues the call flow establishment which is terminated by the mobile phone.
209: IWS-1xBS sends an A21 interface event notification message to HRPD AN, to remind that its MS/AT is currently receiving the service from the 1x network. IWS-1xBS starts the timer Tack-21.
210: HRPD AN sends an A21 interface Ack (A21-Ack) message to IWS-1xBS, and IWS-1xBS stops the timer Tack-21.
From the above call flow, it is described that, when MS/AT is in HRPD system, how to send the voice paging from the 1x system to the mobile phone via the air interface of the HRPD system, so that it can turn to the 1x system and establish corresponding services.
However, there may be other HRPD ANs at the AN boundary where the MS/AT in idle state is located. With the movement of the MS/AT at the boundary, a back and forth registration, or so-called ping-pong effect, will occur between different ANs. In order to effectively curb and reduce such ping-pong effect and promote the paging mechanism between many different AN boundary areas as well as improve the success ratio of paging the MS/AT, the air interface of the prior art HRPD defines a Secondary Color Code scheme, which can ensure that one AN is able to page a MS/AT which is in the service area of other ANs. This technology has been applied to the packet data service originated by the HRPD network but has not been applied to delivery of the voice service paging from the 1x by the HRPD network, especially the delivery of the voice service paging from the 1x in the HRPD network when the MS/AT is at many AN boundaries of HRPD, and the current access network technologies have not solved this problem.